Various mat cutter systems have been disclosed in the prior art for making the cutting of mats easier. For example, in U.S. Pat. No. 4,413,542 (Rempel) a mat cutter and guide system is provided which includes a rectangular cutting base and a novel clamping frame. A cutting blade is mounted on the base between adjustable stops. A repeater and duplicator adjustment mechanism is also provided in order to cut different widths of the sides of the mat opening as well as to provide a second mat with a slightly smaller opening.
Disclosed in U.S. Pat. No. 3,527,131 (Ellerin et al) is a mat cutter device for trimming art mats. The mat cutter includes a ways in which a cutter is mounted. Above the ways is a rod on which suitable stops are adjustably located to define the length of the cut as the cutter moves between the two stops. Located to one side of the base is a straight edge ruler which acts as a squaring stop for locating a work piece and as a scale by which to set a depth stop. Another mat cutter provided with stops for the cutter blade is disclosed in U.S. Pat. No. 3,996,827 (Logan). Adjustable stops are also provided on the squaring angle in order to locate the edge of the picture mat at a desired position. Still another cutter device with stops for a cutting mechanism is disclosed in U.S. Pat. No. 3,213,736 (Keeton).
In U.S. Pat. No. 4,505,174 (Carithers, Jr.), an automatic mat cutting apparatus is disclosed in which the size of the opening to be cut is adjustable. It is further disclosed that suitable switches or stops can be connected to the control means to precisely control the length of travel of each mat cutter. The position of the cutting blade can also be adjusted simply by moving the support thereof left to right to provide for the cutting of double mats.
Although the various mat cutting systems described above have been designed to make the cutting of picture mats easier, such systems have not proven adequate for all the varieties of openings to be cut in picture mats. In addition, the repeatability of certain cuts is limited by the requirement that exact placement of certain of the stops must be mainly repeated and this leads to a source of error in attempting to duplicate cuts.